HotshardLearn ↗Write-Ahead LogWRITECHECKPOINTCRASHRECOVER

Write-Ahead Log — pick a scenario

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Watch for

The log filling as you write, emptying at the checkpoint, then — after the crash wipes memory — the data file plus the replayed log rebuilding the exact same state.

More about this scenario
You'll learn

How a write-ahead log lets a database survive a crash without losing a single acknowledged write.

How it runs

Each write is appended to the log on disk before it touches memory. A checkpoint folds memory into the data file and truncates the log; a crash wipes only memory; recovery reloads the checkpoint and replays the log.